Due in part to the prevalence of computers and other digital devices, large numbers of digital documents exist and many more are being created daily. Determining the subject matter of the digital documents may help in finding, organizing, storing, summarizing, analyzing, or otherwise using the digital documents.
The subject matter claimed in the present disclosure is not limited to embodiments that solve any disadvantages or that operate only in environments such as those described above. Rather, this background is only provided to illustrate one example technology area where some embodiments described in the present disclosure may be practiced.